Development of non-invasive sensory and probes to monitor lung cell function in vivo will provide novel information on the pathophysiology of lung diseases. This will enable rationales for prophylactic or therapeutic intervention approaches to be developed based on the measured cellular abnormality. In this Phase I proposal, an in vivo, non-disruptive, Fiber Optics Laser Doppler system (FOLDS) will be constructed to measure two parameters of ciliary activity in realtime namely, ciliary beat frequency (CBF) and metachronal wave period (MWP). These parameters are fundamental to effective mucociliary transport. The sensing probe will pass through the sampling channel of a fiber-optic broncho-endoscope. A fiberoptic prototype will be developed utilizing dynamic laser light scattering in conjunction with the time-frequency and time-scale analyses (wavelet). CBF and MWP will be determined in native ciliated epithelia and in dogs. In Phase II, this system will be packaged and tested in humans. We envision that this will be used during routine trachael-bronchoscopy and endoscopic paranasal maxillary examination in patients in ambulatory care units and in hospitals. It will provide the first in vivo quantitative information. This will support qualitative visual clinical assessment and eliminate the need for biopsies for in vitro determination of CBF. PROPOSED COMMERCIAL APPLICATION This system will be used in nasal and lung diseases that exhibit impairment of mucociliary transport. The system is also applicable to assess most types of biological motilities, velocity flow profile of fluids as well as remote measurements of physical vibrations.